> I don't think there is any harm in calling set_page_writeback(),> redirty_page_for_writeback() and end_page_writeback() in the case where> there is no I/O to submit, and some dirty data cannot be written. It is> consistent with what happens in __block_write_full_page().> > It's also possible that some part of the page was written, and another> part cannot be, causing the page to be redirtied.

You are right. I revisited the code and there's nothing wrong withyour patch :-)